Macroscopic and microscopic characteristics of an African Blastomyces dermatitidis strain

This report describes the macro- and microscopic characteristics of a strain of Blastomyces dermatitidis isolated in an Italian hospital from a Libyan patient suffering from cutaneous blastomycosis. The fungus was isolated with great difficulty because of the presence of a Proteus species on the lesion. Conversion of the mycelial into the yeast-like phase achieved the best results, using Columbia ANC culture medium. After 5-6 days, this transformation was only partial and presented swollen hyphae and yeast-like cells. The biological characteristics were typical of B. dermatitidis strains of African origin. The differences between African and North American strains are confirmed, in agreement with findings already reported in the literature.